Cleaner silencer



March 5, 1957 w w MCMULLEN 2,783,857

CLEANER SILENCER Filed Sept. 27, 1954 2 Sheets-Sheet l INVENTGF! ATTORNEY March 5, 1957 w. w. yMGMULLEN 2,783,857

CLEANER SILENCER Filed sept. 21, 1954 2 shets-sheet 2 INVENTOR Uni-ted- Sffes Paten "o CLEANER SILEN CER Wesley W. McMullen, Flint, Mich., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware 'lhis invention relates to air cleaners and silencers in general and more particularly to unitary cleaner silencer structures for use with air induction means such as automotive engines and the like.

Numerous advantages are obtained in providing a unitary cleaner silencer structure for use with automotive engines. Such -advantages include a more compact assembly, fewer assembled parts, a saving in materials, a saving in manufacture time, and a more operationally satisfactory unit.

It is now proposed to provide a unitary cleaner silencer structure having a minimum number of separable parts. It is proposedto provide a silencer element which includes a wall common to a cleaner element adapted to be removably secured thereto. lt is proposed to provide an oil wetted tilter through which air is inducted and to provide passages and chambers through which the air will then flow and within which objectionable sounds will be eliminated. It is proposed to provide an air flow passage having a minimal resistance to such flow and to which would cause a resistance to such flow. Such measures are proposed to be accomplished without an intricate arrangement of parts but by a simple and effective arrangement of walls, chambers and passages in a cooperative manner to provide the desired result.

In the drawings:

Figure l is a side elevational view of a unitary cleaner' silencer structure embracing the principle of this invention and having parts broken away and shown in crosssection.

provide against sudden expansions of the air Figure 2 is a top plan view of the cleaner silencer of v Figure l with parts broken away to better illustrate the interior of the structure.

The cleaner silencer 10 comprises an outer casing 12 including a silencer element 14 and a cleaner element 16.

The silencer element 14 is formed by concentric cylindrical walls or sleeves 18 and 20. The innermost sleeve 20 is centrally retained near the bottom of the other sleeve 18 by annular walls 22 and 24 secured to the innermost sleeve and extending outwardly towards the outer cylindrical wall or sleeve 18. The annular walls 22 and 24 are secured to the sleeve 20 in spaced relation to each other and are engaged together at their outer edges with the lower end of the cylindrical wall 18, which is crimped over as at 26 and beaded as at 28, to hold the walls together. The lower annular wall 22 includes an inner annular dished portion 30 and an outer annular portion 32 inclined upwardly with a shoulder 34 therebetween. The annular wall 24 is sloped downwardly to engage wall 22 and forms a chamber 36 therewith. A plurality of apertures 38 are formed through the inner sleeve 20 for communication with the chamber 36 which is thereby adapted to act as a tuned resonator chamber.

An upwardly extending divergent conical tube 40 is secured to the innermost sleeve 20. The outer walls of the tube 40 with the cylindrical wall 18 form an annular chamber 42, opening upwardly, of a predetermined acoustical capacitance.

The upper end of the silencer 14 is covered by a closure or end casing 44. The end casing 44 includes an upper wall 46 and a lower wall 48 with the upper wall formed to provide a continuous side wall 50 extending laterally towards the lower wall and being formed as at 52 to engage the edge of the lower wall thereto. The end casing 44 is an elongated member, as shown in Figures l and 2, being circular at one end with a relatively large opening formed in the lower wall 48 and surrounded by a flange 54 for telescoping engagement with the cylindrical wall 18 to close the upper end of the silencer' element. The other portion of the end casing 44 is extended lateraily to one side to provide an elongated and relatively wide outlet passage 56 and includes an outlet opening 58 formed in the lower wall 48 which may be connected to the induction system of an engine or other device. A flange 60 is provided about the outlet opening 58 and is slotted as at 62 to provide means for connecting the structure to the induction passage of any device with which the cleaner silencer is adapted to be used. Attaching means 64 ange 60 means.

The extended portion of the casing 44 over the outlet opening S8 is provided with an inner sound absorbing liner 66 which is formed to tit the inside surface of the wall 50 which, in this instance, is obliquely disposed to direct induction air through the outlet opening. The sound absorbing liner 66 may be constructed in any suitable manner as by providing a filter body of sound absorbing material 68 Within a perforated wall 70 extending across the end of the casing The wall 70 may be provided with flanged portions 72 which may be welded or otherwise secured to the side wall Si) as is indicated at 74. The sound absorbing material may be employed to absorb high pitch, hissing sounds that may emanate from the induction means through the outlet opening 58.

The cleaner element 16 includes a dished cover member 76 which is adapted to be secured to the silencer e1ement 14. A depending threaded bolt 78 is secured centrally within the sleeve 2t) by strap means 80 secured transversely thereacross as by welding as at 82. The threaded bolt 78 extends centrally through the cover member 76 with a Wing bolt 84 threaded on its lower end to retain the cover member in spaced relation to the lower annular wall 22 of the silencer element. The cover member 76 includes spaced outer and inner walls 86 and 88 with the inner wall 88 having open pie-shaped or other openings 9i) formed therein to expose the sound absorbing liner 92 disposed betv een the walls. The outer wall 86 of the cover member 76 is formed to provide an annular shoulder 94 against which the outer periphery of the sound absorbing liner $2 is engaged and thereby centered.

A filter element 96, including an annulus or ring of filter material 98 having filter screens 100 concentrically disposed on opposite sides thereof, is retained between the wall 22 and the cover member 76. The upper end of the filter element 96 is engaged upon the outer annular portion 32 of wail 22 between the shoulder 34 and the crimped over edges of wall 2t", 22 and 24 as shown at 26. The peripheral edge of the cover member 76 is bent over as at 102 to retain the lower end of the lter ele ment 96.

The cleaner siiencer assembly 10 as employed with induction means connected to opening 58 is adapted to draw air through the filter element 96 into the collecting chamber 104 between annular wall 22 and the cover member 76. The air passes through the conduit or sleeve 18 and over apertures 38. The resonating chamber 36 is for tightening the flange around such induction may be extended around thev adapted -to attenuate objectionable sounds of certain frequencies originating in the induction system.

` Theair 4then passes through the divergiing conical tube 40. The divergence of the tube 4t? allows for a gradual eivipansion o f the air as it leaves the tube, which expansion if Vsudden would cause resistance to air how. rlf'he air passes through tube 4d without a sudden change in the air velocity as it enters the outlet passage or chamber 56 formed in the end casing f-i. rhis Vvarrangement lowers the resistance to the ow of air and consequently increases the power output of the induction means.

The upwardly opening annular chamber 42 is coupled at its open upper end to the sound transmitting path formed by the outlet passage 54, tube 40 and sleeve 2%. The yacoustical capacitance of the chamber 42 is such as will attenuate objectionable noises which might otherwise pass from the outlet passage 54 down through the tube 40 Vas in its normal transmission path.

I claim:

l. A cleaner silencer unit comprising a cleaner Ielement and a silencer element having a common separating wall, said cleaner element including a dished cover member secured in spaced relation to said separating wall and having an annular filter element disposed between said wall and member to form an air collecting chamber therewith, said silencer element including concentric cylindrical walls and spaced annular walls secured together to form a resonator chamber and an acoustical capacitancel chamber, the innermost of said cylindrical walls providing a flow conduit having apertures formed therethrough for access to said resonator chamber and being divergently formed in the direction of air ow through said cleaner silencer to allow for the gradual expansion o f induction air passing therethrough and being in open communication with said collecting chamber 0f said cleaner element, and an elongated end casing sesuted over the @aast sa@ Qt sa@ silente; @1r-meat an hvigva'outlet passage fo'rrned therein, said outlet passage being in unobstructed open communication with said acoustical capacitance chamber and the outlet end of said iiow conduit, said acoustical capacitance chamber with said resonator chamber and divergent flow conduit being adapted to attenuate objectionable noises within said cleaner silencer unit.

2. A cleaner silencer assembly including a cleaner element and an outlet air passage member having a silencer element secured therebetween, a divergent conduit concentrically disposed within said silencer element and extending from said, cleaner element towards said outlet air passage member, said conduit being divergent in the direction of air flow through said assembly and converging in a direction opposite to the sound transmitting path therethrough, and an annular acoustical capacitance chamber formed by said conduit and the outer wall of said silencer element, said capacitance chamber being in unobstructed open communication with said passage mem. ber for the greater attenuation of objectionable sounds received within said assembly.

'3. The cleaner silencer assembly of claim 2 which further includes a resonator chamber provided between said silencer and cleaner elements and formed by adjacently disposed walls thereof and a plurality of apertures-,formed through said conduit and in communication with saidv resonator chamber.

Cummings Oct.'l2, 1937v Brown May 27, 1941 

